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Hexahydropyrrolo[3,4-b]indoles 6, 10, and 13 are obtained from 2-bromo-3-carboxamides 5, 9, and 12, respectively, by a 1,5-radical translocation process followed by 5-endo-trig cyclization to the indole C-2 position. We wish to describe a new synthesis of hexahydropyrrolo[3,4b]indoles from 2-bromoindole-3-carboxamides involving sequential indole C-2 radical generation, 1,5-hydrogen atom abstraction, and 5-endo-trig cyclization to the indole C-2 position. In connection with our interest in pyrrolo[3,4b]indoles 1 and indolo[2,3-a]quinolizidines, 2 we envisioned the free radical sequence shown in Scheme 1 as an attractive route to these ring systems.

A short, protecting group-free total synthesis of bruceollines D, E, and J has been achieved. The enantioselective reduction of bruceolline E with β-chlorodiisopinocampheylborane delivers both the natural and unnatural enantiomers of bruceolline J in excellent yields and enantioselectivities. Reduction with baker's yeast and sucrose was shown to provide the unnatural enantiomer of bruceolline J in 98% ee.

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